di ketahui barisan artimetika U3 = 8 dan U50= 149 tentukan suku pertama

U3 = a + 2b = 8
U50 = a + 49b = 149

a + 49b = 149
a + 2b = 8
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47b = 141
b = 141/47
b = 3

a + 2b = 8
a + 2.3 = 8
a + 6 = 8
a = 8 - 6
a = 2

a = U1 = 2

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